Taylor Edrington, co-owner of Royal Gorge Anglers and SoCO Fishing Guides, wets a line on the Arkansas River on Monday. With steady, wadable flows and rising water temperatures, the caddis are coming to life and the trout are coming quickly to the net on the Arkansas River above Canon City this week. Scott Willoughby, The Denver Post

Among the casualties: Peru Creek east of the Keystone ski area has been pronounced “biologically dead.”

State environmental officials also have listed 32 sites along the Animas River in critical condition. Some headwaters of the Arkansas River, too, are “virtually devoid of any aquatic life.”

The source of the contamination is abandoned mines — about 500,000 across the West, at least 7,300 in Colorado. Federal authorities estimate that the headwaters of 40 percent of Western rivers are tainted with toxic discharge from abandoned mines.

Colorado Department of Natural Resources records show 450 abandoned mines are known to be leaking measurable toxins into watersheds. So far, 1,300 miles of streams have been impaired.

But as bad as the damage is, community watershed groups, mining companies and even state agencies contend they cannot embark on cleanups for fear of incurring legal liability.

Under the Clean Water Act, parties who get involved at abandoned mines and accidentally make matters worse — even over the short term — could be vulnerable to federal prosecution for polluting waterways without a permit.

Obama administration officials two years ago promised to break gridlock on this issue, spurring a legislative fix to enable “good Samaritan” cleanups and devoting “significant resources” for watershed restoration.

Interior Secretary Ken Salazar last week acknowledged there is still gridlock and that more must be done to deal with tens of thousands of leaking abandoned mines nationwide.

“There’s a significant lack of funding to be able to move forward at the moment, but we remain committed to the proposition that these abandoned mines need to be cleaned up,” Salazar said in an interview.

Looking west from Denver up Bear Creek and Clear Creek canyons, “you can see the huge number of abandoned mines there that continue to contribute to bad water quality in Clear Creek and in the South Platte,” he said. “We need to work on it.”

U.S. Sen. Mark Udall has declared he now will renew the push, first by pressuring Environmental Protection Agency officials to use their administrative discretion and assure good Samaritan watershed groups and mining companies that, if they embark on cleanups, they won’t be punished.

EPA officials “might be able to assure good Samaritans that they might be safe from potential liability,” Udall said. Beyond that, “you need legislative change. That would really unleash good Samaritans to go to work.”

The damage to Western waterways “is significant. It’s acidic,” Udall said. “It threatens drinking water and agricultural water supplies. It ends up polluting streams, in some cases to the extent they’re devoid of any life. This is a downward spiral that we need to avoid at all costs.”

EPA officials say they are unable to commit. In 2007, the EPA put forth model “comfort letters” designed to partially shield watershed groups from liability under the Superfund law, which regulates the cleanup of toxic-wastes sites.

The letters, however, don’t address liability under the Clean Water Act.

Mining industry leaders have recognized a need to address the toxic legacy of mining under the 1872 Mining Law, which still applies, letting hard-rock miners extract minerals without paying taxes or royalties.

The Colorado Mining Association supports reforms to enable private sector participation in cleanups — as long as companies won’t face “excessive royalties or roadblocks to mine development,” said CMA president Stuart Sanderson.

Today’s gridlock deeply frustrates leaders in some mountain communities where, for years, watershed groups have been ready to restore ruined streams.

“In short, perfect is the enemy of the good,” said Elizabeth Russell, manager of mine-restoration efforts for the conservation group Trout Unlimited.

State records show:

• Colorado’s 7,300 abandoned mine sites contain about 17,000 point sources of pollution, such as open mine shafts and tunnels.

• The abandoned mines are scattered widely — including Jamestown west of Boulder and the headwaters of the Mancos River in the southwestern corner of the state.

Meanwhile, economic development groups are interested in reviving mining — seeking the jobs mining might provide. Mining traditionally has paid better than the retail work that many residents of mountain towns now must accept to get by.

Federal and state laws passed in the 1970s establish safeguards that should be sufficient to prevent mining companies from abandoning mines in the future, said Loretta Pineda, director of Colorado’s Division of Mining Reclamation and Safety.

“A new mine has to protect the hydrological balance. Whatever they’re going to disturb, they’re going to have to reclaim,” Pineda said.

“The past mines are the problem. There’s nobody to do the cleanup work. How are we going to do that?”

Bruce Finley covers environment issues, the land air and water struggles shaping Colorado and the West. Finley grew up in Colorado, graduated from Stanford, then earned masters degrees in international relations as a Fulbright scholar in Britain and in journalism at Northwestern. He is also a lawyer and previously handled international news with on-site reporting in 40 countries.

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